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POWrap a delegate with a delegate that has a different signature, at runtime (not compile time)
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  1. POWrap a delegate with a delegate that has a different signature, at runtime (not compile time)
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    copied!<p>I'm trying to wrap a lambda Func&lt;bool&gt; with a Func&lt;T,bool&gt; where T is only known at runtime. I'm not looking to actually emit code that does anything with that parameter, it's just going to be ignored and the wrapped method would be called.</p> <p>For instance if I have:</p> <pre><code>Func&lt;bool&gt; innerFunc = () =&gt; true </code></pre> <p>At runtime I need to do something like this:</p> <pre><code>Type paramType = typeof (String); // or any other Type Type wrappedFuncType = typeof (Func&lt;,&gt;).MakeGenericType (paramType, typeof (bool)) // this next line is close to what I want to do but isn't correct Delegate wrappedFunc = Delegate.CreateDelegate (wrappedFuncType, this, innerFunc.Method); </code></pre> <p>I've seen some code using LambdaExpression.Compile which could possibly work, but because this code is in a PCL targeting .NET 4.5, SL4+, WP7+, WinStore it doesn't look like it's available.</p> <p><strong>TL;DR</strong></p> <p>How do I wrap Func&lt;bool&gt; delegate so that it matches something like Func&lt;String,bool&gt; and that calls to the outer delegate returns the value from the inner delegate?</p> <p><strong>UPDATE</strong> Thanks to @usr, I got it working like this:</p> <pre><code>private static Func&lt;T, bool&gt; WrapFuncBool&lt;T&gt; (Func&lt;bool&gt; func) { return _ =&gt; func (); } private Delegate CreateParameterizedFuncBoolDelegate (Type parameterType) { var wrapMethodInfo = this.GetType().GetMethod ("WrapFuncBool", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod (parameterType); return (Delegate) wrapMethodInfo.Invoke (this, new object[] { (Func&lt;bool&gt;) (() =&gt; true) }); } </code></pre>
 

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